Tottenham manager Andre Villas-Boas is waiting to discover the extent of the ankle injury suffered by Jan Vertonghen in their friendly defeat to Sunderland in Hong Kong.

Villas-Boas was left sweating on the fitness of Vertonghen ahead of the start of the new Barclays Premier League season after the Belgium international was stretchered off after landing awkwardly on a pitch which the Spurs boss admitted he had concerns about.

The 26-year-old defender is due to undergo an MRI scan today to determine the extent of the problem and Villas-Boas will be keeping his fingers crossed the injury is not too serious.

"He might have sprained the ligaments in his left ankle. We need to have an MRI to see the full extent. But there is some range of movement in the ankle so we hope it won't be that long," Villas-Boas said after the match.

"We hope he will be back for the first game of the season."

Kick-off at the Hong Kong Stadium was delayed for half an hour by torrential rain which left surface water on the pitch, and the match was ultimately restricted to two 40-minute halves.

Villas-Boas, whose side lost the game 3-1 to their Premier League rivals, said he was worried about the conditions.

"I was concerned. But what can you do? The pitch is what it is. It's always like that for this tournament. You can't change the conditions. They are extremely poor," he added.